Embodiments of the invention relates to a pump assembly with the features specified below. Such pump assemblies are known and are mostly applied as circulation pumps for hot potable water circulation. Since the hot water circulation is typically only required for a brief period, specifically mostly only during the day and often also only at specific times, it is common in a few heating installation controls, to switch off the circulation pump in times, in which it is not required, in order in this manner to reduce the heat losses in the circulation conduit.
For circulation pumps which are applied in an independent manner, it is counted as belonging to the state of the art to provide a time control on the pump itself, so that at the pump itself, one may set the times at which the pump is switched on, and the times at which the pump is switched off. Such a pump is, for example, described in “Grundfos Circulation Pump Comfort UP 15-14 BUT”. With regard to this, a mechanical time switch is provided at the face-end of the pump housing, and this time switch, as is common with such mechanical time switches, comprises a ring moved by clockwork, on which riders (slides) are arranged at a quarter of an hour or half an hour intervals, which may be brought from an inner to an outer position, wherein these riders activate a mechanical switch which switches the motor of the pump on or off, depending on the rider position.
Such time controls have proven their worth, since they are quasi self-explanatory and may also be set by the amateur without operating instructions. However, the disadvantage thereby is the fact that the mechanical clockwork as well as the mechanical switch require some effort with regard to manufacture and are prone to error. Moreover, the electrical clockwork requires energy.
Electronic time switches are known, with which the mechanical switch is replaced by an electronic one, and an electronic, typically a digital clock is provided, which has a display which displays the time and/or switch times and may be programmed via buttons. A disadvantage of these time switches however is the fact that the setting and programming as a rule is only possible after careful study of the operating instructions. Moreover, the display is comparatively costly and is also prone to breakdown, in particular with humid room atmospheres. With a failure of the display, the pump assembly may practically no longer be used independently of its switch function.